Laravel5.5问题：SQLSTATE[42000] Syntax error or access violation 1071 Specified key was too long; max k

Laravel5.5 配置后台管理包Voyager问题：SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 1000 bytes

听说voyager不错，新建立一个文件尝试了一下，

D:\wamp64\www\laravel\myproject λ> php artisan voyager:install –with-dummy

Setting up the hooks

Hooks are now ready to use! Go ahead and try to "php artisan hook:install test-hook"
Publishing the Voyager assets, database, language, and config files
Copied Directory [\vendor\tcg\voyager\publishable\assets] To [\public\vendor\tcg\voyager\assets]
Copied Directory [\vendor\tcg\voyager\publishable\database\migrations] To [\database\migrations]
Copied Directory [\vendor\tcg\voyager\publishable\database\seeds] To [\database\seeds]
Copied Directory [\vendor\tcg\voyager\publishable\demo_content] To [\storage\app\public]
Copied Directory [\vendor\tcg\voyager\publishable\lang] To [\resources\lang]
Publishing complete.
Publishing complete.
Migrating the database tables into your application
Migration table created successfully.

 [Illuminate\Database\QueryException]
  SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 1000 bytes (SQL: alter table users add unique users_email_unique(email))

  [Doctrine\DBAL\Driver\PDOException]
  SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 1000 bytes

  [PDOException]
  SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 1000 bytes

问题让人头大，根据laravel官方的文档，更改laravel5.5的文件（ ../app/providers/appServiceProvider.php）内容 , 如下